Some of these questions, says Greely, focus on ethical issues related to donors. For example, given the long life span of human embryonic stem cell lines, and their likely use in clinical practice, will it really be possible to promise donors anonymity? "It seems highly likely," says Greely, "that the Food and Drug Administration will want as much information as possible about the donor's health, not only with regard to pathogens that may infect the donated cells but also about diseases with genetic or family links."
Other questions relate to deriving cell lines (for example how "old" an embryo may be used to make cell lines?), and to the appropriate use of human embryonic stem cells (under what circumstances, for example, is it ethically permissible to create human/nonhuman chimeras?).
Researchers and their institutions, he says, will also have to deal with complicated legal, ethical, and political questions concerning property and stem cells, both intellectual property and "personal" property.
The legal and ethical issues associated with human embryonic stem cell research, says Greely, will impose great and often unprecedented burdens on the researchers, administrators, and even lawyers for any institution that embarks on it. "Coping with these issues will be painful but not handling them well will be worse, for individual researchers and institutions and for science as a whole."